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3 years ago

9

a car travels West 50km for 2 hours before heading south at a rate of 30 km per hour for 1.5 hours. What is the car's average sp

eed?

1 answer:

inn [45]3 years ago

6 0

Answer:

Explanation:

average speed is distance traveled over time

v = (50 + 30(1.5)) / (2 + 1.5) = 27.1428571...

v = 27 km/hr

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A beam of light strikes a sheet of glass at an angle of 56.6° with the normal in air. You observe that red light makes an angle

Yuri [45]

Answer:

(a). Index of refraction are $n_{red}$ = 1.344 & $n_{violet}$ = 1.406

(b). The velocity of red light in the glass $v_{red} =$ 2.23 × $10^{8} \ \frac{m}{s}$

The velocity of violet light in the glass $v_{violet} =$ 2.13 × $10^{8} \ \frac{m}{s}$

Explanation:

We know that

Law of reflection is

$n_1 \sin\theta_{1} = n_2 \sin\theta_{2}$

Here

$\theta_1$ = angle of incidence

$\theta_2$ = angle of refraction

(a). For red light

1 × $\sin 56.6$ = $n_{red}$ × $\sin 38.4$

$n_{red}$ = 1.344

For violet light

1 × $\sin 56.6$ = $n_{violet}$ × $\sin 36.4$

$n_{violet}$ = 1.406

(b). Index of refraction is given by

$n = \frac{c}{v}$

$n_{red}$ = 1.344

$v_{red} = \frac{c}{n_{red} }$

$v_{red} = \frac{3(10^{8} )}{1.344}$

$v_{red} =$ 2.23 × $10^{8} \ \frac{m}{s}$

This is the velocity of red light in the glass.

The velocity of violet light in the glass is given by

$v_{violet} = \frac{3(10^{8} )}{1.406}$

$v_{violet} =$ 2.13 × $10^{8} \ \frac{m}{s}$

This is the velocity of violet light in the glass.

8 0

3 years ago

When the magnetic flux through a coil of wire changes, what is generated between the ends of the coil? Which equation predicts t

True [87]

Answer:

induced electromotive force (Voltage) E = - N dΦ / dt

Explanation:

When the magnetic flux this coil induces a current in each turn of the coil, which is why an induced electromotive force (Voltage) appears at the ends of the coil.

This phenomenon is fully explained by Faraday's law

E = - dΦ / dt

where in the case of a coil with N turns of has

E = - N dΦ / dt

Rl flux is the product of the normal to the area by the magnetic field, in this case the flux changes so we can assume that the area of the coil is constant

4 0

3 years ago

The view that there are no universal moral principles or standards that hold true for all people is referred to as

pav-90 [236]

I think this fits the definition of ethical relativism. does that sound right?

8 0

3 years ago

A bicyclist travels 4.5 km west, then travels 6.7 km at an angle 27.0 degrees South of West. What is the magnitude of the bicycl

Dimas [21]

Answer:

<em>10.90km</em>

Explanation:

Magnitude of the total displacement is expressed using the equation

d = √dx²+dy²

dx is the horizontal component of the displacement

dy is the vertical component of the displacement

dy = -6.7sin27°

dy = -6.7(0.4539)

dy = -3.042

For the horizontal component of the displacement

dx = -4.5 - 6.7cos27

dx = -4.5 -5.9697

dx = -10.4697

Get the magnitude of the bicyclist's total displacement

Recall that: d = √dx²+dy²

d = √(-3.042)²+(-10.4697)²

d = √9.2538+109.6146

d = √118.8684

<em>d = 10.90km</em>

<em>Hence the magnitude of the bicyclist's total displacement is 10.90km</em>

<em></em>

6 0

2 years ago

What happens to the current in a circuit if the resistance triples? If the voltage triples?

Sauron [17]

(Example 1 )
<span>If the Voltage that furnishes the current is an ideal (no internal resistance) Voltage source. Then; </span>

<span>V/R = i </span>
<span>V/2R = i/2 If external resistance doubles, current reduced to 1/2 of original value </span>
<span>V/3R = i/3 If external resistance triples, current reduced to 1/3 of original value </span>

<span>(Example 2) </span>
<span>But if the Voltage that furnishes the current is a practical [contains an internal resistance (Ri)] Voltage source. Then the current is a function of the Voltage source`s internal resistance, which does not double nor triple, plus the external resistance which is being doubled and tripled. </span>

<span>V/(R + Ri) = i </span>
<span>V/(2R + Ri) = greater than i/2 but less than I. </span>
<span>V/(3R + Ri) = greater than i/3 but less than i/2</span>

7 0

3 years ago